DE102007020568A1 - Process for the continuous preparation of aminoalkyl-containing organopolysiloxanes - Google Patents

Abstract

A process for the preparation of aminoalkyl-containing organopolysiloxanes by (i) reacting (A) linear, cyclic or branched organopolysiloxanes with (B) aminoalkylsilanes having a SiC-bonded, basic nitrogen-containing hydrocarbon radical and two or three hydrolyzable groups, or their partial or full hydrolysates, if appropriate in the presence of (C) basic catalysts and optionally (D) chain terminating reagents and (ii) optionally subsequent to the reaction (i) neutralization of the optionally used basic catalysts (C) with the proviso that compounds (A), ( B) and optionally (D), if appropriate in the presence of catalyst (C), are reacted continuously in a reaction space whose length to diameter ratio is equal to or greater than four.

Description

The The invention relates to a process for the preparation of aminoalkyl groups having organopolysiloxanes.

aminoalkyl carrying organopolysiloxane oils, hereinafter referred to as amine oils are among the most important organically functionalized Organopolysiloxanes and are used in many different applications used successfully. These include u. a. the textile equipment, building protection, cosmetic formulations or treatment of surfaces. For most applications in these In areas it is important to use amine oils, the one high quality. To the corresponding quality characteristics count a) a constant and as low as possible Residual volatility (eg caused by short-chain Alcohols, short-chain and / or cyclic siloxane components or Amines), b) a constant viscosity, c) an optimal one statistical distribution of the aminoalkyl groups in the copolymer, and, where possible and necessary, d) optical clarity (turbidity). Above all, the quality features b) and c) can usually only by achieving effective equilibration of the polymer mixture, optionally coupled to a condensation reaction, but depending on the set reaction conditions different amounts of volatile Connections are incurred.

amine oils are usually by condensation and / or equilibration reactions between linear or cyclic organopolysiloxanes and aminoalkyl-functionalized Alkoxysilanes or their partial or full hydrolysates hergstellt, usually under the action of catalytic amounts of basic inorganic or organic compounds.

To The current state of the art are amine oils in the so-called batch process, thus campaign-wise in discontinuous Agitator processes, manufactured. Agitators are due to the variety of chemicals that can be used in them Reactions are very flexible, however - are compared with continuous process - at very large Production campaigns and high mass throughput uneconomical. This is mainly because they are only to a certain extent Automate degrees and that you can heat up for a long time and cooling and for filling and emptying the several cubic meters large container in purchase take (high operating costs, high labor costs). additionally must stand life of the reaction product accepted be in which z. B. the quality of the produced material is performed. But above all inevitably result from the various production campaigns Fluctuations in product composition and quality, whereby product specifications must be broader and high qualities can be more difficult to achieve. Last but not least, it takes a stirrer compared to one continuously operated plant significantly more space to complete and can only be achieved by very large technical Increase effort or not at all throughput ("upscaling", "debottlenecking").

One difficulty with common amine oil syntheses is the deactivation of the condensation or equilibration catalyst used. If the basic catalyst is neutralized in a conventional manner with an acid, such as. In US 5,077,421 described, it comes by Salzausfällungen to turbidity. However, continuous or semi-continuous filtration of a continuously produced amine oil is undesirable because of technical difficulties (eg, filter change in continuous operation) and reduced space-time yield.

One way to avoid such turbidity is the method of deactivating the tetraalkylammonium hydroxides or ammonium phosphates and borates used after completion of the reaction by thermal decomposition, as z. In US 4,652,662 (corresponding DE-A 3418358 ) is described. However, the resulting decomposition products must be removed by distillation in vacuo. It is known to the person skilled in the art that this can be a process section which takes several hours and is also energy-intensive and which can not be carried out continuously without further ado because of the resulting residence time problem. Moreover, traces of volatile organic amines usually lead to an unacceptable odor nuisance when using the produced amine oils.

US 7,129,369 (corresponding EP-A 1580215 ) describes a process in which, despite the use of alkali metal hydroxides and alcoholates without a filtration step, cloudless amine oils are obtained by neutralizing with silyl phosphates, thereby obtaining silicone-soluble neutralization products.

US 4,128,568 (corresponding DE-A 2705563 ) describes a continuous process for producing position of unfunctionalized organopolysiloxanes. The alkali metal hydroxides used must be deactivated by addition of trimethylchlorosilane. The organopolysiloxanes thus obtained must therefore be subjected to a subsequent filtration and distillation step in order to remove the volatile disiloxanes produced by the deactivation and thus to achieve the desired low residual volatility.

EP-A 1723193 describes a catalyst-free continuous process for the continuous preparation of terminal aminoalkyl-functional siloxanes from terminally SiOH-bearing siloxanes and cyclic silazanes. However, the process starts with cyclic silazanes from a special and expensive amine precursor, inter alia with the aim of keeping the resulting amine oil free of volatile alcohols resulting from condensation reactions. In addition, the siloxanes bearing SiOH groups necessary for pendant amine oils produced by this process are not readily and readily available.

Continuous methods, such. In US 3,853,934 in which the Organopolysiloxanbausteine to be condensed are passed over an acidic silicate fixed bed catalyst, separate for the production of amine oils, since the amine groups with the acid groups spontaneously form salts and deactivate the catalyst.

EP-A 0982347 describes a continuous process for the preparation of silicone polymers from siloxanes or siloxane cycles carrying SiOH groups by means of catalytic amounts of basic phosphazenes. However, apart from end group functionalization with various SiC-bonded hydrocarbon radicals, no heteroatom-substituted organically functionalized copolymers, such as amine oils, are described.

A very special continuous reactor for the preparation of siloxane polymers from siloxane mono- and oligomers is disclosed in US Pat EP-A 0522776 described. The reaction mixture is foamed and passes through a porous wall in the reaction space. Due to the high generated interface between the reaction mixture and the gas space, volatilities from thin media can be removed well. However, the process described is limited to condensation reactions of monomers or low-viscosity oligomers, an explicit equilibration of the polymers produced or the production of high-viscosity silicone oils is not described. In addition, a conventional neutralization of the catalysts is described which i. A. leads to cloudy products by salt formation.

all The methods described above have in common that those generated thereby Amine oils do not simultaneously in the main quality characteristics Residual volatility, equilibrium quality and possibly turbidity as well as their constancy a satisfactory and above all constant Deliver result. Downstream filtration or devolatilization steps or a post-processing by equilibration would be necessary.

It The task was to provide a method in which the aforementioned disadvantages are avoided, and in the aminoalkyl groups having organopolysiloxanes with constant product properties obtained, in particular with low and constant residual volatility, constant desired viscosity and more constant statistical distribution of the aminoalkyl-containing siloxane units in the polymer, resulting in avoidance of block structures of these units and thus means a good equilibrium quality. The task is solved by the invention.

• (i) Umsetzung von
• (A) linearen, cyclischen oder verzweigten Organopolysiloxanen mit
• (B) Aminoalkylsilanen, die einen SiC-gebundenen, basischen Stickstoff aufweisenden Kohlenwasserstoffrest und 2 oder 3 hydrolysefähige Gruppen aufweisen, oder deren Teil- oder Vollhydrolysate, gegebenenfalls in Gegenwart von
• (C) basischen Katalysatoren und gegebenenfalls
• (D) Kettenterminierungsreagenzien und
• (ii) gegebenenfalls anschließend an die Umsetzung (i) Neutralisation der gegebenenfalls eingesetzten basischen Katalysatoren (C)

mit der Maßgabe, dass Verbindungen (A), (B) und ggf. (D) gegebenenfalls in Gegenwart von Katalysator (C) kontinuierlich in einem Reaktionsraum umgesetzt werden, dessen Verhältnis Länge zu Durchmesser gleich vier oder größer ist.The invention relates to a process for the preparation of aminoalkyl-containing organopolysiloxanes by

• (i) Implementation of
• (A) linear, cyclic or branched organopolysiloxanes with
• (B) Aminoalkylsilanen, which have a SiC-bonded, basic nitrogen-containing hydrocarbon radical and 2 or 3 hydrolyzable groups, or their partial or full hydrolysates, optionally in the presence of
• (C) basic catalysts and optionally
• (D) chain terminating reagents and
• (ii) optionally subsequent to the reaction (i) neutralization of the optionally used basic catalysts (C)

with the proviso that compounds (A), (B) and optionally (D) are optionally in the presence of catalyst (C) be reacted continuously in a reaction space whose length to diameter ratio is equal to four or greater.

at the method according to the invention are the compounds (A), (B), optionally (C) and optionally (D), preferably continuously passed the reaction space and there are the compounds (A), (B) and optionally (D), if appropriate in the presence of the catalyst (C) for the reaction brought, and from the reaction space are continuously so dissipated containing aminoalkyl organopolysiloxanes.

Preferably the reaction takes place (i) in the presence of basic catalysts (C).

Subsequently the reaction (i) is preferably carried out continuously, the neutralization the basic catalysts (C).

Preferably the reaction space has a ratio of length to diameters of 4 to 1000, preferably 5 to 100, more preferably 6 to 10.

Of the Term organopolysiloxanes is intended in the context of the present invention both dimeric and oligomeric as well as polymeric siloxanes include.

With the method of the invention can Amine oils arbitrarily possible amine number can be generated. The Amine number corresponds to the number of ml of a 1M HCl, the Neutralizing 1 g of substance is required, and is in millimoles Amine groups are given per gram of substance. Preferably, the amine number range between 0.001 and 12.5, preferably the range between 0.01 and 5, more preferably the range between 0.1 and 3 mmol amine groups per gram of substance.

The Viscosities of the inventive Process produced amine oils can be between water and stable consistency. The viscosity, always measured at 25 ° C, is preferably 1 mPa · s to 10,000,000 mPa.s, preferably 100 mPa.s to 100,000 mPa · s, more preferably 500 mPa · s to 50,000 mPa · s.

to Implementation of the method according to the invention are the starting compounds used for the preparation of the amine oils (A), (B) and optionally (D) passed through a chamber whose ratio Length / diameter is equal to four or higher. Such a chamber can be used, for example, in loop reactors, kneaders, Extruders, flow tubes, tube reactors, microreactors or centrifugal pumps, as well as in any combinations thereof be. Experience has shown that the procedure in the extruder or kneader especially for producing highly viscous or Stable amine oils (viscosity measured at 25 ° C greater than 50,000 mPa · s), the procedure in the tubular reactor, especially for the production of flowable amine oils (viscosity measured at 25 ° C less than 50,000 mPa · s). The procedure in the extruder or kneader for the production of highly viscous or stable amine oils (in 25 ° C measured viscosity greater than 50,000 mPa · s) is therefore preferred, the procedure in the tubular reactor for the production of flowable amine oils (viscosity measured at 25 ° C less than 50,000 mPa · s) is particularly preferred.

at the process of the invention, the starting materials and optionally the catalyst is preferably continuous in the reaction space conveyed or pumped and mixed therein, the educts and optionally the catalyst before reaching the reaction space or the union in the reaction space can be preheated. For preheating are u. a. electric heating jackets and wires that surround the educt leads as well as either double-walled educt feed lines through which a heated medium flows or single-walled educt feeds through the bath of a heated Medium gone. If the catalyst does not react with the educts in the reaction space is brought, it may possibly be one in the reaction space immobilized or applied to an optionally polymeric carrier act basic catalyst. The individual volume flows the educts with each other are adjusted appropriately, to make the desired statistical distribution more functional Groups in the polymer as well as the desired product molecular weight distribution to obtain. The total volume flow is directed throughout the reactor after the desired residence time in the reactor. The reaction space can be heated and mixed as a whole or even partially or kneaded. For heating u. a. electrical Heating jackets and wires covering the reaction space surrounded or a double-walled reaction space, which is heated by a Medium is flowed through. For mixing are suitable u. a. so-called static mixer, which are mounted in the reaction space can, or mechanically driven stirrer (power transmission directly for B. via a shaft or a combination of Magnetic coupling and shaft) or gas streams (eg nitrogen), cause the turbulence.

The Material of the reactor may be of metal, such as chromium-vanadium-steel reactors, enamelled steel reactors to glass reactors vary.

The Reactions in the reaction space are preferably carried out at a temperature from 50 to 180 ° C, preferably 80 to 130 ° C.

The Reaction times and thus the average residence times amount preferably 1 to 180 minutes, preferably 10 to 120 minutes and more preferably 20 to 90 minutes.

Furthermore the pressure in the reaction space can be at any, the respective Reactor type adjusted value, with values between the atmospheric pressure surrounding the reactor (about 1013 mbar) and 0.1 mbar, values between 100 and 1 mbar in particular are preferred to the possibly occurring during the reaction volatile components continuously over the Remove gas phase by distillation. In support of the Distillative removal of volatile components may be additional a so-called purge gas stream is passed through the reaction space, wherein the inert nitrogen gas is preferred.

To reaction, d. H. after passing through the reaction zone in the desired residence time, which is optionally in the reaction mixture existing catalyst (C) deactivated. This can be z. B. by chemical Reaction of the catalyst with a deactivator - mostly a neutralizing agent or inhibitor - carried out or but by thermal deactivation, adding the reaction mixture a specially brought to the necessary temperature zone of the Reactor goes through. If through the reaction or the catalyst deactivation solids in the subsidized Reaction product are located, so they can be done by downstream Procedures are removed. In such downstream process it can be a continuous filtration or a continuous Extraction with a suitable solvent or a continuous Adsorptive process on a suitable adsorbent act.

To passing through a cooling zone in which the reaction product by the heat exchange principle to a desired Temperature was cooled, the reaction product can be continuous bottled in storage container or end container or be continuously fed to other parts of the system, such as B. a continuous dispersing device for the production from those obtained by the process according to the invention Amine containing dispersions.

In a preferred embodiment of the method according to the invention (numbers in parentheses refer to 1 ), the starting compounds (A), (B) and optionally (D) and the catalyst (C) from corresponding containers ( 1 ) via pumps or pump / balance combinations ( 2 ) continuously by preheater ( 3 ) and then through a heatable reactor ( 5 ). Through a nitrogen supply ( 4 ) may optionally be switched on a purge gas stream to remove low boilers. The reactor contains one or more stirrers or static mixing elements ( 6 ) and one or more perforated or sieve trays ( 7 ). In a cold trap ( 8th ) low boilers with the aid of a regulated vacuum pump ( 9 ) are condensed. After passing through the product ( 10 ) is removed from the deactivator container ( 11 ) metered in the deactivator of the catalyst and the product in a stirred product collection tank ( 12 ) collected and cooled.

As organopolysiloxanes (A), in the process according to the invention those are preferably selected from the group of linear polydiorganosiloxanes of the general formula HOR ₂ SiO (R ₂ SiO) _x SiR ₂ OH (I) and R ₃ SiO (R ₂ SiO) _y SiR ₃ (II) cyclic polydiorganosiloxanes of the general formula (OSiR ₂ ) _z (III) and their mixtures used,
wherein R may be the same or different and represents a monovalent optionally halogenated hydrocarbon radical having 1 to 18 carbon atoms,
x is 0 or an integer from 1 to 800, preferably 10 to 450, more preferably 30 to 150.
y is 0 or an integer from 1 to 800, preferably 10 to 450, particularly preferably 30 to 150, and
z is an integer from 3 to 12.

Within or along the siloxane chain of the siloxanes of the formulas (I) - (III) given above, which is usually not represented by such formulas, other siloxane units may be present in addition to the diorganosiloxane units R ₂ SiO. Examples of such other, mostly only as impurity present siloxane units are those of the formulas RSiO _3/2 , R ₃ SiO _1/2 and SiO ₂ , wherein R has the meaning given.

Preferably be in the inventive method the Organopolysiloxanes (A) in amounts of 99.99 to 0.1 wt .-%, preferably 99.9 to 51 wt .-%, particularly preferably 99 to 18 wt .-%, respectively based on the total weight of the reaction mixture of (A), (B), (C) and possibly (D) used.

Preferably, in the process according to the invention as aminoalkylsilanes (B) are those of the general formula X _n R _(3-n) SiZ (IV) and their partial or full hydrolyzates used,
in which
R has the meaning previously given,
X is a hydrolysable group selected from the group of -OR ¹ , -NR ' ₂ and -Cl, preferably -OR ¹ ,
R ^{1 represents} a monovalent alkyl radical having 1 to 18 carbon atoms which may be substituted by one or two ether oxygen atoms,
R 'is hydrogen or a monovalent hydrocarbon radical having 1 to 18 carbon atoms,
Z represents a monovalent SiC-bonded, basic nitrogen-containing hydrocarbon radical and
n is 2 or 3.

Examples of hydrocarbon radicals R, R ¹ or R 'are alkyl radicals, such as the methyl, ethyl, n-propyl, iso-propyl, 1-n-butyl, 2-n-butyl, isobutyl, tert-butyl, n-pentyl, iso-pentyl, neo-pentyl, tert-pentyl, hexyl, such as the n-hexyl, heptyl, such as the n-heptyl, octyl, such as the n-octyl radical and iso-octyl radicals, such as the 2,2,4-trimethylpentyl radical, nonyl radicals, such as the n-nonyl radical, decyl radicals, such as the n-decyl radical, dodecyl radicals, such as the n-dodecyl radical, and octadecyl radicals, such as the n-octadecyl radical; Cycloalkyl radicals such as cyclopentyl, cyclohexyl, cycloheptyl and methylcyclohexyl radicals; Aryl radicals, such as the phenyl, naphthyl, anthryl and phenanthryl radicals; Alkaryl radicals, such as o-, m-, p-tolyl radicals, xylyl radicals and ethylphenyl radicals; and aralkyl radicals, such as the benzyl radical, the α- and the β-phenylethyl radical.

The hydrocarbon radicals R, R ¹ or R 'optionally contain an aliphatic double bond. Examples are alkenyl radicals, such as the vinyl, allyl, 5-hexen-1-yl, E-4-hexen-1-yl, Z-4-hexen-1-yl, 2- (3-cyclohexenyl) ethyl and cyclododeca-4,8-dienyl. Preferred radicals R having an aliphatic double bond are the vinyl, allyl, and 5-hexen-1-yl radicals. Preferably, however, at most 1% of the hydrocarbon radicals R contain one double bond.

Examples halogenated radicals R are haloalkyl radicals such as 3,3,3-trifluoro-n-propyl radical, the 2,2,2,2 ', 2', 2'-hexafluoroisopropyl radical, the heptafluoroisopropyl radical and haloaryl radicals, such as the o-, m- and p-chlorophenyl.

Prefers the radical R is a monovalent hydrocarbon radical with 1 to 18 carbon atoms, with the methyl radical being particularly preferred is.

Examples of R ¹ are CH ₃ -, CH ₃ CH ₂ -, (CH ₃ ) ₂ CH-, CH ₃ CH ₂ CH ₂ -, CH ₃ CH ₂ CH ₂ CH ₂ -, CH ₃ CH ₂ OCH ₂ CH ₂ - , CH ₃ CH ₂ OCH ₂ - and CH ₃ OCH ₂ CH ₂ radicals.

Preferably Z in formula (IV) is a radical of the formula -R ² - [NR ³ -R ⁴ -] _g NR ³ ₂ .

where R ^{2 is} a divalent linear or branched hydrocarbon radical having 1 to 18 carbon atoms,
R ^{3 has} the meaning of R ¹ or denotes an acyl radical, preferably a hydrogen atom,
R ^{4 is} a divalent hydrocarbon radical having 1 to 6 carbon atoms and
g is 0, 1, 2, 3 or 4, preferably 0 or 1.

Preferred examples of radicals Z are:
H ₂ N (CH ₂ ) ₃ -
H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) ₃ -
H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) CH (CH ₃ ) CH ₂ -
(Cyclohexyl) NH (CH ₂ ) ₃ -
CH ₃ NH (CH ₂ ) ₃ -
(CH ₃ ) ₂ N (CH ₂ ) ₃ -
CH ₃ CH ₂ NH (CH ₂ ) ₃ -
(CH ₃ CH ₂ ) ₂ N (CH ₂ ) ₃ -
CH ₃ NH (CH ₂ ) ₂ NH (CH ₂ ) ₃ -
(CH ₃ ) ₂ N (CH ₂ ) NH (CH ₂ ) ₃ -
CH ₃ CH ₂ NH (CH ₂ ) ₂ NH (CH ₂ ) ₃ -
(CH ₃ CH ₂ ) ₂ N (CH ₂ ) ₂ NH (CH ₂ ) ₃ -
and their partially or fully acylated forms.

Examples of aminoalkylsilanes (IV) are
(3-aminopropyl) dimethoxymethylsilane,
(3-aminopropyl) diethoxymethylsilane,
3-aminopropyl) trimethoxysilane,
(3-aminopropyl) triethoxysilane,
[N- (2-aminoethyl) -3-aminopropyl] dimethoxymethylsilane,
[N- (2-aminoethyl) -3-aminopropyl] diethoxymethylsilane,
[N- (2-aminoethyl) -3-aminopropyl] trimethoxysilane,
[N- (2-aminoethyl) -3-aminopropyl] -triethoxysilane,
(Aminomethyl) dimethoxymethylsilane,
(Aminomethyl) diethoxymethylsilane,
(Aminomethyl) trimethoxysilane,
(Aminomethyl) triethoxysilane.
Particularly preferred
[N- (2-aminoethyl) -3-aminopropyl] dimethoxymethylsilane,
[N- (2-aminoethyl) -3-aminopropyl] trimethoxysilane and
(3-aminopropyl) dimethoxymethylsilane
and their cyclic or linear partial or full hydrolysates.

Prefers Aminoalkylsilanhydrolysate (B) from aminoalkylfunktionellen Dialkoxysilanes, such as (3-aminopropyl) dimethoxymethylsilane or [N- (2-aminoethyl) -3-aminopropyl] dimethoxymethylsilane, produced by hydrolysis in water.

As Aminoalkylsilanhydrolysate (B) are therefore preferably those of the general formula HO (ZRSiO) _m H (VI) used
where R and Z are as defined above and
m is an integer from 2 to 50.

Preferably are aminoalkylsilanes (B) or their partial or full hydrolysates in amounts of 0.01 to 99.9%, preferably 0.1 to 82% and especially preferably used 1 to 49%, in each case based on the total weight the polysiloxanes (A) and optionally (D) used.

When Basic catalysts (C) can be condensation and equilibration catalysts used in the inventive method become.

Preferably are as basic catalysts (C) alkali or alkaline earth metal hydroxides, -Oxides, -alcoholates or -siloxanolate used previously be dissolved in a suitable solvent.

Prefers are used as basic catalysts (C) alkali metal hydroxides, alkali metal alcoholates, Alkali metal siloxanolates and mixtures used.

Examples for alkali metal hydroxides are potassium hydroxide and sodium hydroxide.

Examples for alkali metal alcoholates are sodium methoxide and sodium ethanolate.

Examples for alkali siloxanolates are sodium siloxanolates.

Prefers Be potassium or sodium hydroxide (optionally in the solvent Methanol or water), and sodium methoxide (optionally in the solvent Methanol).

The Basic catalysts (C) are preferably used in amounts of 1 to 1000 ppm by weight, preferably 10 to 400 ppm by weight, particularly preferably 30 to 200 ppm by weight, in each case based on the total weight of the reaction mixture from (A), (B), (C) and optionally (D) used.

If in the inventive method reactive Si-OH-terminated Polysiloxanes of the formula (I) can be used, in addition a chain termination reagent (D), a so-called stopper or stopper siloxane, be used. In principle, all compounds are suitable for this, which can react with Si-OH groups and with respect their reactivity with Si-OH groups are monofunctional or can form such monofunctional groups. About that In addition, these chain terminating reagents may be further functional Wear groups that do not contain the Si-OH groups or the aminoalkyl groups react, and in case of further implementation of the produced by the process according to the invention amine oil be reacted to additional effects too achieve.

When Chain termination reagent (D) are used in the inventive Process preferably those selected from the group monoalkoxysilanes, aminomonoalkoxysilanes, linear and cyclic silazanes, Alcohols, short chain linear diorganopolysiloxanes and mixtures thereof used.

To count z. Monoalkoxytrialkylsilanes, (aminoalkyl) monoalkoxydialkylsilanes, linear or cyclic silazanes, alcohols, short chain linear polydiorganosiloxanes or mixtures thereof.

Examples of monoalkoxytrialkylsilanes are those of the formula R ₃ Si (OR ¹ ) (VII) and Examples of (aminoalkyl) monoalkoxydialkylsilanes are those of the formula R ₂ ZSi (OR ¹ ) (VIII) wherein R, R ¹ and Z have the meaning given above.

Examples of alcohols are those of the general formula H- [O (CHR ⁵ ) ₁ ] _k OR ⁶ (IX) where R has the meaning given above,
R ^{5 may be the} same or different and represents a hydrogen atom or a C ₁ to C ₁₈ hydrocarbon radical,
R ^{6 is} a C ₁ - to C ₃₀ -hydrocarbon radical or a group of the general formula - (C = O) -R ⁷ , where R ^{7 is} a radical R ⁵ or OR ⁵ ,
l 2, 3 or 4 and
k is 0 or an integer from 1 to 100.

Examples of short chain linear polydiorganosiloxanes as chain terminating reagent (D) are short chain triorganosiloxy endblocked polydiorganosiloxanes of the formula R ₃ SiO (SiR ₂ O) _v SiR ₃ (X) and short chain hydroxy or alkoxydiorganosiloxy terminated polydiorganosiloxanes of the formula (R''O) R ₂ SiO (SiR ₂ O) _w SiR ₃ (XI) where R has the meaning given above,
R '' is a hydrogen atom or a radical R ¹ ,
v is 0 or an integer from 1 to 150, preferably 30 to 100, and
w is 0 or an integer from 1 to 150, preferably 30 to 100, and
If a stopper or stop siloxane (D) is used as the chain terminating reagent in the process according to the invention, this is preferably used in amounts of 0.01 to 50%, preferably 0.05 to 30% and particularly preferably 1 and 20%, in each case based on the total weight the reaction mixture of (A), (B), (C) and (D) used.

The Deactivation of the basic catalyst (C) can be achieved by the addition of neutralizing agents (E), which react with the basic catalysts Form salts. Such neutralizing agents may, for. B. Be carboxylic acids or mineral acids. Prefers are carboxylic acids, such as methane (formic acid), ethane (Acetic acid), propionic acid.

The Deactivation of the basic catalyst (C), however, is preferred by the addition of neutralizing agents (E) with the basic Catalysts form salts which in the resulting amine oils are soluble and thus produce no turbidity. Examples of such neutralizing agents (E) are long chain At room temperature, liquid carboxylic acids, such as n-octanoic acid, 2-ethylhexanoic acid, n-nonanoic acid and oleic acid, hexadecane and octadecanoic acid, Carbonic acid esters such as propylene carbonate, or carboxylic anhydrides such as octenyl succinic anhydride.

Further examples of neutralizing agents (E) which form salts with the basic catalysts which are soluble in the amine oils obtained and thus do not produce turbidity are triorganosilyl phosphates, preferably trimethylsilyl phosphates and triorganophosphates, preferably mixtures of mono-, di- and tri-isotridecyl phosphates (available at the label Hordaphos ^® MDIT in Fa. Clariant). Preferred trimethylsilphosphates are compositions consisting essentially of
0-50 wt .-% monosilyl phosphate of the formula: [(CH ₃ ) ₃ SiO] (HO) ₂ P = O
20-100 wt .-% disilyl phosphate of the formula: [(CH ₃ ) ₃ SiO] ₂ (HO) P = O
0-70% by weight of trisilyl phosphate of the formula: [(CH ₃ ) ₃ SiO] ₃ P = O
the total amount being 100% by weight. The necessary amount of neutralizing agent (E) depends on the amount of basic catalysts (C) used and is preferably 0.05 to 0.50%, preferably 0.15 to 0.30%, in each case based on the total weight of the reaction mixture (A), (B), (C) and optionally (D). The neutralization can be carried out before or after the cooling of the reaction mixture.

The obtained by the process according to the invention Aminoalkyl-containing organopolysiloxanes (amine oils) have a residual volatility of preferably less than 4 wt .-%, preferably less than 2 wt .-%, more preferably less as 1% by weight.

The Residual volatility is a thermally determined value and is defined as the amount of volatiles in% by weight when heating a sample amount of 5 g at 120 ° C in a time of 60 min (120 ° C / 5 g / 60 min).

A large part of the volatile constituents are cyclic siloxanes, which in addition to higher cycles octamethyltetrasiloxane (D ₄ ) is included.

A particularly preferred embodiment of the invention Process provides amine oils with extraordinary low residual volatilities, preferably less than 2%, preferably less than 1 wt .-%, with a particularly low average Residence times, preferably between 1 and 50 minutes without a reduced pressure compared to the surrounding of the reactor Atmospheric pressure must be applied to the reactor. at this particularly preferred embodiment of the invention Process are as aminoalkylsilanes (B) partial and Vollhydrolysate the aminoalkylsilanes (B), preferably aminoalkylsilane hydrolyzates of Formula (VI) used. Preferred in this process are organopolysiloxanes (A) of the formulas (I) and / or (II) together with the Aminoalkylsilanhydrolysaten (B), preferably of the formula (VI) used.

The inventive method has the advantage that Aminoalkyl-containing organopolysiloxanes (amine oils) with constant product quality, especially a low one and constant residual volatility, a constant desired Viscosity and a good and constant equilibrium quality (Prevention of block structures of the aminoalkyl groups in the aminoalkyl groups having organopolysiloxanes). By the use of suitable Neutralizing agent (E) can, if desired is obtained, in particular haze-free amine oils become.

By the method according to the invention are preferably aminoalkyl-containing organopolysiloxanes of the general formula (R ⁸ O) _q R _3-q SiO (ZRSiO) _o (R ₂ SiO) _p SiR ₃ -q (OR ⁸ ) _q (XII) where R and Z are as defined above,
R ^{8 is} a hydrogen atom or R ¹ ,
o is an integer from 1 to 1000, preferably from 2 to 260,
p is an integer from 0 to 2500, preferably from 50 to 650
q is 0 or 1.
receive.

The obtained by the process according to the invention Aminoalkyl group-containing organopolysiloxanes can among other things as means for the treatment of porous or non-porous, absorbent or non-absorbent Substrates such as leather, nonwovens, cellulosic materials (Pule & Paper), textiles, non-wovens and tissues, natural and artificial fibers, Glasses and ceramics, porous mineral building materials, Building coatings and wood and as part of polishing and Coating compositions for z. B. painted and not painted Metals, plastics and laminates are used, the described Substrates by the treatment with the according to the invention Method obtained aminoalkyl groups bearing organopolysiloxanes main characteristics such as hydrophobicity and / or softness be lent. Furthermore, the according to the invention Process resulting aminoalkyl-containing organopolysiloxanes inter alia as part of defoamer formulations, for paper sizing and plasterboard coating, as a care product for painted and unpainted metals, plastics, Laminates, gums and rubbers, as dispersing aids, as Wetting agents, as separating (auxiliary) agents, as paint additives, as PU foam stabilizers as well as in the field of personal care as active ingredients in hair treatments, Hair shampoos and skin care products are used. The after the according to the invention obtained aminoalkyl groups carrying organopolysiloxanes can be dissolved in organic solvents or dispersed in water, preferably be used in the form of aqueous emulsions. It can obtained by the process according to the invention Aminoalkyl group-containing organopolysiloxanes in the free Amine form or in salt form, such as ammonium chloride salt or ammonium carboxylate salt by the addition of hydrochloric acid or the corresponding carboxylic acid are used. Compositions according to the invention Process resulting aminoalkyl-containing organopolysiloxanes may contain other ingredients, such as surfactants, Thickeners, rheology-modifying additives, perfumes, Waxes, emollients, detergents, lubricating oils, electrolytes, flavorings, Biocides, pharmaceutical or cosmetic agents.

It follow selected examples which illustrate the invention should. However, the invention itself is by no means to this Examples limited. Those used in the examples Percentages in the determination of residual volatilities (120 ° C / 5 g / 60 min) are by weight. All indicated viscosities were measured at 25 ° C.

For Examples 1-6 was used as a continuous reactor Glass tubular reactor (inside diameter 80 mm, height 500 mm, Ratio length / diameter = 6.25, volume approx. 2.5 L). The reactor was in several, through PTFE well plates separated zones and equipped with a stirrer. The educts and the catalyst (to reaction parameters and proportions see following tables of the respective examples) were the passage of tempering units heated to the specified temperatures and in the proportions continuously over Pump systems adjusted to the reactor temperature and pressure Promoted reaction zone.

The Termination of the reaction was by continuous metering achieved a deactivator at a fixed position in the tubular reactor. This position was in the area of the product flow after leaving the heated reaction zone.

from that the average residence time of the reaction mixture in the reaction zone, promoted by the total throughput of Educts is determined. From the volume of the reactor of about 2.5 L results, for example, at a throughput of 2.5 L / h average residence time of 1 h, at a throughput of 1.25 L has an average residence time of 2 h.

Of the Product discharge took place in a cooled and stirred Collecting container to the deactivator evenly in the product and to cool the product.

Comparative Experiment 1 (discontinuous):

To prepare a cloud-free amine oil having an amine number of 0.25 and a viscosity of 200-220 mPa.s, the following starting materials were used in accordance with Table 1a and b: TABLE la polydimethylsiloxane HO-SiMe ₂ - (O-SiMe ₂ ) ₄₀ -OH (Aminoalkyl) silane [N- (2-aminoethyl) -3-aminopropyl] dimethoxy-methyl-silane Stoppersiloxan Me ₃ Si (O-SiMe ₂ ) ₂₃ -OSiMe ₃ catalyst Sodium methoxide in methanol (30% by weight) deaktivator Tris (trimethylsilyl) phosphate Table 1b: amount used Wt .-% Vol .-% polydimethylsiloxane 872 g 80.73 80.83 (Aminoalkyl) silane 26.5 g 2:45 2.31 Stoppersiloxan 179 g 16:57 16:59 catalyst 0.67 g 12:06 12:08 deaktivator 0.6 g 12:19 12:18

In a 2-L three-necked flask (ratio length / diameter = 1) with mechanical stirrer, internal thermometer and reflux condenser was a mixture of 872 g of polydimethylsiloxane, 26.5 g of (aminoalkyl) silane, 179 g of stopper siloxane and 0.67 g of catalyst solution under Stirring at a reduced to 50 mbar pressure to 80 ° C. heated. The volatile components were in a with liquid nitrogen cooled cold trap collected. After 90 minutes, the plant was nitrogen stream brought to normal pressure, the deactivator added and stirring cooled. This gave a colorless haze-free Amine oil.

The following Table 1c summarizes the analytical data of experiments carried out independently of each other according to the previous procedure, using the same batches of starting materials. Table 1c: attempt 1 2 3 4 Standardabes. Residual volatility of the product [%] 4.6 5.3 5.4 4.3 12:46 Viscosity [mPa · s] 238 183 155 220 32.2

Example 1:

In contrast to Comparative Experiment 1, a reaction mixture of the same educt volume distribution according to Table 2a was passed under the following reaction parameters through the tubular reactor according to the invention described above: The product outlet and the continuous catalyst deactivation took place after an average residence time of 90 min. After a run time of the reactor of 10 h, the system was brought to room pressure and emptied the product container. A colorless turbid-free oil was obtained. Table 2a: Flow rate polydimethylsiloxane 80.83 Vol .-% Flow rate (aminoalkyl) silane 2.31 Vol .-% Flow rate stopper 16.59 Vol .-% Flow rate of catalyst 0.08 vol.% Flow rate deactivator 0.18% by volume Reactor temperature 80 ° C Temperature tempering unit polydimethylsiloxane and (aminoalkyl) silane 80 ° C Temperature temperature control stopper 50 ° C reactor pressure 50 mbar

During the runtime of the reactor, samples of the reaction product were taken. Table 2b below summarizes the analytical data of the samples, using the same batches of starting materials as in Comparative Experiment 1. Table 2b: sample 1 2 3 4 5 6 Standardabes. Residual volatility of the product [%] 3.5 3.3 3.4 3.3 3.5 3.4 12:08 Viscosity [mPa · s] 210 228 219 224 221 224 5.7

High resolution ²⁹ Si NMR studies of Samples 1-6 revealed excellent equilibrium quality, block structures of the [N- (2-aminoethyl) -3-aminopropyl] methylsiloxy units were not observed. The comparison of the standard deviations of the residual volatilities obtained under comparative experiment 1 and example 1 and viscosities clarifies the more constant product quality of the amine oils obtained by the process according to the invention (example 1). In addition, the absolute residual volatilities of the resulting amine oils are lower by the process according to the invention (Example 1), which additionally contributes to increased product quality.

Comparative experiment 2 (ratio Length / diameter = 1.56):

The Experiment under Example 1 was repeated, but the one used was Tubular reactor with the same diameter of length 500 mm (ratio length / diameter = 6.25) on the Length 125 mm (ratio length / diameter = 1.56). The residence time was 90 min.

During the runtime of the reactor, samples of the reaction product were taken. The following Table 3a summarizes the analytical data of the samples using the same batches of starting materials as in Example 1. Table 3a: sample 1 2 3 4 5 6 Standardabes. Residual volatility of the product%] 5.2 4.7 5.0 4.2 5.5 4.9 12:41 Viscosity [mPa · s] 94 104 125 116 93 96 12.0

The resulting viscosities of Samples 1-6 were significantly too low, indicating that the desired product was not obtained. The residual volatilities of the samples were significantly increased and varied more than in Example 1. In addition, there was post-opacities in all samples. High-resolution ²⁹ Si NMR studies revealed insufficient equilibrium quality of all samples.

Example 2:

The following starting materials according to Table 4a were used. Table 4a: Polydimethylsiloxane of the type HO-SiMe ₂ - (O-SiMe ₂ ) ₄₀ -OH (Aminoalkyl) silane [N- (2-aminoethyl) -3-aminopropyl] dimethoxy-methyl-silane stopper n-hexyl glycol catalyst Sodium methoxide in methanol (30% by weight) deaktivator Tris (trimethylsilyl) phosphate

The product outlet and the continuous catalyst deactivation took place after an average residence time of 90 min. After a running time of the reactor of 6 h, the system was brought to room pressure and emptied the product container. This gave a colorless haze-free oil with a viscosity of 1450 mPa · s, a volatility (120 ° C / 5 g / 60 min) of 1.09 wt .-% and an amine number of 0.27. High resolution ²⁹ Si NMR studies revealed no block structures of the [N- (2-aminoethyl) -3-aminopropyl] methylsiloxy units.

The educt quantities and process parameters are summarized in Table 4b. Table 4b: Flow rate polydimethylsiloxane 95.0 vol.% Flow rate (aminoalkyl) silane 2.7% by volume Flow rate stopper 2.0 vol.% Flow rate of catalyst 0.1 vol.% Flow rate deactivator 0.2 vol.% Reactor temperature 85 ° C Temperature tempering unit polydimethylsiloxane and (aminoalkyl) silane 85 ° C Temperature temperature control stopper 50 ° C reactor pressure 50 mbar

Example 3:

The following starting materials according to Table 5a were used. Table 5a: Polydimethylsiloxane of the type HO-SiMe ₂ - (O-SiMe ₂ ) ₄₀ -OH (Aminoalkyl) silane [N- (2-aminoethyl) -3-aminopropyl] dimethoxy-methyl-silane catalyst Sodium methoxide in methanol (30% by weight) deaktivator Hordaphos ^® MDIT

The product outlet and the continuous catalyst deactivation took place after an average residence time of 90 min. After a running time of the reactor of 6 h, the system was brought to room pressure and emptied the product container. This gave a colorless haze-free oil with a viscosity of 1250 mPa · s, a volatility (120 ° C / 5 g / 60 min) of 0.53 wt .-% and an amine value of 0.30. High resolution ²⁹ Si NMR studies revealed no block structures of the [N- (2-aminoethyl) -3-aminopropyl] methylsiloxy units.

The educt quantities and process parameters are summarized in Table 5b. Table 5b: Flow rate polydimethylsiloxane 97.1% by volume Flow rate (aminoalkyl) silane 2.9 vol.% Flow rate of catalyst 0.02 vol.% Flow rate deactivator 0.03 vol.% Reactor temperature 80 ° C Temperature tempering unit polydimethylsiloxane and (aminoalkyl) silane 80 ° C reactor pressure 250 mbar

Example 4:

The following starting materials according to Table 6a were used. Table 6a: Polydimethylsiloxane of the type HO-SiMe ₂ - (O-SiMe ₂ ) ₂₄₅ -OH (Aminoalkyl) silane hydrolyzate (3-aminopropyl) -dimethoxymethyl-silane hydrolyzate catalyst Potassium hydroxide in ethanol (20% by weight) deaktivator acetic acid

The product outlet and the continuous catalyst deactivation took place after an average residence time of 10 min. After a running time of the reactor of 6 h, the system was brought to room pressure and emptied the product container. This gave a colorless oil with a viscosity of 6700 mPa · s (25 ° C), a volatility (120 ° C / 5 g / 60 min) of 0.21 wt .-% and an amine value of 0.16. High-resolution ²⁹ Si NMR studies revealed no block structures of the (aminopropyl) methylsiloxy units.

The educt quantities and process parameters are summarized in Table 6b. Table 6b: Flow rate polydimethylsiloxane 98.1% by volume Flow rate (aminoalkyl) silane hydrolyzate 1.8% by volume Flow rate of catalyst 0.1 vol.% Flow rate deactivator 0.01% by volume Reactor temperature 100 ° C Temperature control unit polydimethylsiloxane and (aminoalkyl) silane hydrolyzate 100 ° C reactor pressure no vacuum

Example 5:

The following starting materials according to Table 7a were used. Table 7a: Polydimethylsiloxane of the type Me ₃ Si (O-SiMe ₂ ) ₃₁₀ -OSiMe ₃ (Aminoalkyl) silane hydrolyzate (3-aminopropyl) -dimethoxymethyl-silane hydrolyzate catalyst Potassium hydroxide in ethanol (20% by weight) deaktivator acetic acid

The product outlet and the continuous catalyst deactivation took place after an average residence time of 10 min. After a running time of the reactor of 6 h, the system was brought to room pressure and emptied the product container. This gave a colorless oil having a viscosity of 1100 mPa · s (25 ° C), a volatility (120 ° C / 5 g / 60 min) of 0.62 wt .-% and an amine value of 0.25. High-resolution ²⁹ Si NMR studies revealed no block structures of the (aminopropyl) methylsiloxy units.

The educt quantities and process parameters are summarized in Table 7b. Table 7b: Flow rate polydimethylsiloxane 97.6% by volume Flow rate (aminoalkyl) silane hydrolyzate 2.3% by volume Flow rate of catalyst 0.1 vol.% Flow rate deactivator 0.01% by volume Reactor temperature 100 ° C Temperature control unit polydimethylsiloxane and alkoxysilane 100 ° C (Aminoalkyl) silane hydrolyzate no vacuum

Example 6:

The following starting materials according to Table 8a were used. Table 8a: Polydimethylsiloxane of the type HO-SiMe ₂ - (O-SiMe ₂ ) ₂₄₅ -OH (Aminoalkyl) silane hydrolyzate (3-aminopropyl) -dimethoxymethyl-silane hydrolyzate catalyst Sodium methoxide in methanol (30% by weight) deaktivator acetic acid

The product outlet and the continuous catalyst deactivation took place after an average residence time of 25 min. After a running time of the reactor of 6 h, the system was brought to room pressure and emptied the product container. This gave a colorless oil with a viscosity of 13300 mPa · s (25 ° C), a volatility (120/5 g / 60 min) of 0.20 wt .-% and an amine value of 0.10. High-resolution ²⁹ Si NMR studies revealed no block structures of the (aminopropyl) methylsiloxy units.

The educt quantities and process parameters are summarized in Table 8b. Table 8b: Flow rate polydimethylsiloxane 98.8% by volume Flow rate (aminoalkyl) silane hydrolyzate 1.2 vol.% Flow rate of catalyst 0.02 vol.% Flow rate deactivator 0.01% by volume Reactor temperature 80 ° C Temperature control unit polydimethylsiloxane and (aminoalkyl) silane hydrolyzate 80 ° C reactor pressure no vacuum

Example 7:

The following starting materials according to Table 9a were used. Table 9a: Polydimethylsiloxane of the type HO-SiMe ₂ - (O-SiMe ₂ ) ₄₀ -OH (Aminoalkyl) silane hydrolyzate (3-aminopropyl) -dimethoxymethyl-silane hydrolyzate stopper Me ₃ Si (O-SiMe ₂ ) ₁₄₀ -OSiMe ₃ catalyst Sodium methoxide in methanol (30% by weight) deaktivator Tris (trimethylsilyl) phosphate

The product outlet and the continuous catalyst deactivation took place after an average residence time of 120 min. After a running time of the reactor of 6 h, the system was brought to room pressure and emptied the product container. This gave a colorless haze-free oil with a dynamic viscosity of 56200 mPa · s and an amine value of 0.84. High-resolution ²⁹ Si NMR studies revealed no block structures of the (aminopropyl) methylsiloxy units.

The educt quantities and process parameters are summarized in Table 9b. Table 9b: Flow rate polydimethylsiloxane 80.0 vol.% Flow rate (aminoalkyl) silane hydrolyzate 8.8 Vol .-% Flow rate stopper 10.8 vol.% Flow rate of catalyst 0.1 vol.% Flow rate deactivator 0.3% by volume Reactor temperature 130 ° C Temperature control unit polydimethylsiloxane and (aminoalkyl) silane hydrolyzate 110 ° C Temperature tempering unit Me ₃ Si (O-SiMe ₂ ) ₁₄₀ -OSiMe ₃ 50 ° C reactor pressure 200 mbar

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - US 5077421 [0005]
• US 4652662 [0006]
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Claims (11)

Process for the preparation of aminoalkyl groups having organopolysiloxanes (i) Implementation of (A) linear, cyclic or branched organopolysiloxanes with (B) Aminoalkylsilanes containing a SiC-bonded basic nitrogen hydrocarbon radical and 2 or 3 hydrolyzable Have groups, or their partial or full hydrolyzates, possibly in the presence of (C) basic catalysts and optionally (D) Chain Terminating Reagents and (ii) optionally subsequently to the reaction (i) neutralization of any used basic catalysts (C) with the proviso that Compounds (A), (B) and optionally (D), if appropriate in the presence of catalyst (C) are reacted continuously in a reaction space whose Ratio length to diameter equal to four or is larger. Method according to claim 1, characterized in that that the reaction space is part of a reactor selected from the group of tube reactors, loop reactors, kneaders and extruders is. Method according to claim 1 or 2, characterized that compounds (A), (B), optionally (C) and optionally (D) continuously be passed through the reaction space and there the connections (A), (B) and optionally (D) optionally in the presence of the catalyst (C) for Reaction be brought, and from the reaction space continuously the aminoalkyl-containing organopolysiloxanes thus obtained be dissipated. Method according to claim 1, 2 or 3, characterized that the reaction (i) in the presence of basic catalysts (C) is performed. Method according to one of claims 1 to 4, characterized in that as organopolysiloxanes (A) those selected from the group of linear polydiorganosiloxanes of the general formula HOR ₂ SiO (R ₂ SiO) _x SiR ₂ OH (I) and R ₃ SiO (R ₂ SiO) _y SiR ₃ (II) and cyclic polydiorganosiloxanes of the general formula (OSiR ₂ ) _z (III) and mixtures thereof are used, wherein R may be the same or different and is a monovalent optionally halogenated hydrocarbon radical having 1 to 18 carbon atoms, x is 0 or an integer from 1 to 800, y is 0 or an integer from 1 to 800, and z is an integer from 3 to 12. Method according to one of claims 1 to 5, characterized in that as aminoalkylsilanes (B) those of the general formula X _n R _(3-n) SiZ (IV) and their partial or full hydrolysates are used, wherein R has the meaning given above, X is a hydrolysable group selected from the group of -OR ¹ , -NR ' ₂ and -Cl, R ^{1 is} a monovalent alkyl radical having 1 to 18 carbon atoms means, which may be substituted by one or two ether oxygen atoms, R 'is hydrogen or a monovalent hydrocarbon radical having 1 to 18 carbon atoms, Z is a monovalent SiC-bonded, basic nitrogen-containing hydrocarbon radical and n is 2 or 3. Method according to one of claims 1 to 6, characterized in that selected as catalysts (C) such from the group of alkali metal hydroxides, alkali metal alcoholates, Alkalimetallsiloxanolaten and mixtures thereof are used. Method according to one of claims 1 to 7, characterized in that as chain terminating reagents (D) those selected from the group of monoalkoxysilanes, Aminomonoalkoxysilanes, linear and cyclic silazanes, alcohols, short-chain linear diorganopolysiloxanes and mixtures thereof are used. Method according to one of claims 1 to 8, characterized in that as neutralizing agent (E) carboxylic acids, Triorganosilylphosphate and triorganophosphates are used. Method according to one of claims 1 to 9, characterized in that the method at a temperature from 50 to 180 ° C is performed. Method according to one of claims 1 to 10, characterized in that the average residence time in the reaction chamber is 1 to 180 minutes.